This application is a divisional application of, and claims priority to, Ser. No. 09/611,664 filed Jul. 6, 2000, abandoned, and claims priority to Japanese Application No. JP 11-193671 filed Jul. 7, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to a substrate processing method and a substrate processing apparatus, for example, for forming a layer insulating film or the like on a substrate.
In the process of fabricating a semiconductor device, so-called multilayer interconnection in which electrode wiring such as aluminum wiring is formed in multiple layers on the front surface of a substrate such as a semiconductor wafer (hereinafter referred to as xe2x80x9ca waferxe2x80x9d) is performed. In the multilayer interconnection, a layer insulating film composed of organic macromolecules and the like is formed between the multilayered electrode wiring, whereby insulation properties between the multilayered electrode wiring are secured.
A spin coating method has been hitherto used to form a layer insulating film. In the spin coating method, a coating solution (a coating solution containing organic macromolecules and the like) which is a raw material for a layer insulating film is supplied to the front surface of a wafer and spread over the entire front surface of the wafer by centrifugal force by rotating the wafer. Then, the wafer is spin-dried by being further rotated, and thereby a layer insulating film composed of organic macromolecules and the like is formed on the front surface of the wafer. Thereafter the wafer is subjected to heat processing, for example, at a temperature of 310xc2x0 C., by stepwise heating over several times, and then to cooling processing.
Incidentally, adhesion promoter (ADP) processing for supplying an ADP solution to the wafer is performed before the coating solution is supplied to the front surface in order to enhance adhesion of the coating solution on the front surface of the wafer, in which case there is a possibility that the front surface temperature of the wafer changes because of the supply of the ADP solution. An excessive drop in the front surface temperature of the wafer because of the performance of the ADP processing, for example, causes drying of the coating solution not to progress, and thus the large quantity of coating solution supplied to the peripheral edge portion of the wafer is cleared off to the surroundings of the wafer by centrifugal force due to the rotation of the wafer. Consequently, the quantity of the coating solution cleared off increases and hence waste increases. Specially in the edge portion of the wafer, a layer insulating film having a sufficient thickness becomes difficult to form. Conversely, an excessive rise in the front surface temperature of the wafer because of the performance of the ADP processing, for example, causes drying of the coating solution to progress excessively, and thus the coating solution does not spread uniformly to the peripheral edge portion of the wafer. As described above, a change in the front surface temperature of the wafer is not favorable since it causes nonuniformity of the layer insulating film. The wafer increases in size these days, and with this increase, harmful effects due to the aforesaid nonuniformity of the layer insulating film and an increase in the quantity of the coating solution to be used become a subject of discussion.
Accordingly, an object of the present invention is to provide a substrate processing method and a substrate processing apparatus each capable of uniformly forming a layer insulating film with a good adhesion on the front surface of a substrate and reducing the quantity of a processing solution to be used.
To settle the aforesaid disadvantages, a first aspect of the present invention is a substrate processing method, comprising the steps of: spreading a first processing solution over the front surface of a substrate; regulating the temperature of the front surface of the substrate over which the first processing solution is spread at a predetermined substrate temperature; and spreading a second processing solution over the front surface of the substrate of which the temperature is regulated at the predetermined temperature.
In the present invention, after the first processing solution is spread over the front surface of the substrate, the temperature of the front surface of the substrate is regulated at the predetermined substrate temperature. Consequently, the second processing solution can be spread while the front surface temperature of the substrate is maintained at the predetermined substrate temperature.
A second aspect of the present invention is a substrate processing apparatus, comprising: a first processing solution supply nozzle for supplying a first processing solution to the front surface of a substrate; a second processing solution supply nozzle for supplying a second processing solution to the front surface of the substrate; a rotary mounting table for mounting the substrate thereon and rotating the substrate; and a temperature regulating mechanism for regulating the temperature of the front surface of the substrate at a predetermined substrate temperature.
These objects and still other objects and advantages of the present invention will become apparent upon reading the following specification when taken in conjunction with the accompanying drawings.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.